Well as you can see, I have recovered all of the posts I lost whilst testing on the site. Luckily I had posted them through NewsGator so I still had a copy of each (it goes without saying that, as I am an IT professional, I didn't have anything backed up). The only long lasting issue is that I have lost all of the comments, so apologies to those of you that shared your thoughts with me. I won't do it again, promise! It also means that those of you reading in some kind of aggregator (SharpReader, NewsGator etc) will probably get all of these posts flagged as unread again.
I reposted them all through the Email Posting Receiver add on I have been knocking up – this lets me send a mail to an address that the blog (based on dotText) is monitoring. The nice thing is that you can have attachments and embedded images in the mail and the tool just does ‘the right thing' with them (that's the theory anyway...)